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The insertion reaction of phenyl isothiocyanate into the Ln-S bond was studied. Phenyl isothiocyanate reacted with [(CH3C5H4)2Sm(SPh)(THF)]2 to give the title complex, (CH3C5H4)2Sm[SC(SPh) NPh](THF),in good yield, which was characterized by elemental analyses, IR, ^1H NMR and X-ray structural determination. The crystal structure analysis of complex shows that samarium atom is coordinated by two CH3C5H4 groups, one O atom of THF, and N and S atoms from the SC(SPh)NPh ligand to form a distorted trigonal-bipyramidal geometry. 相似文献
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循环插入排序法 总被引:2,自引:0,他引:2
唐开山 《计算机工程与应用》2005,41(12):88-91
文章提出了一种循环插入的排序方法。给出了算法思想、算法描述、算法分析和实验结果。其理论意义是改进了一类时间复杂度为O(N2)排序法的时间复杂度,其实用价值是该排序法在一类时间复杂度为O(N2)排序法中排序效率较高的,其平均排序速度比直接插入排序法、选择排序法、冒泡排序快50%~63%。 相似文献
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彭海文 《数字社区&智能家居》2011,(7)
该文先简要介绍了Android平台和Android平台的下的开发,并针对通话拦截和强插所需要的两个知识Broadcast Receiver和Telephony Manager类进行说明,再介绍如何通过AIDL及JAVA反射机制,使用隐藏的ITelephony接口,并研究了通话拦截和强插技术在Android下的实现,最后总结全文,并引出对Android权限管理的一些思考。 相似文献
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刘云忠 《哈尔滨工业大学学报(英文版)》2010,17(4):584-587
Vehicle routing problem with time-varying speed ( VRPTS) is a generalization of vehicle routing problem in which the travel speed between two locations depends on the passing areas and the time of a day. This paper proposes a simple model for estimating time-varying travel speeds in VRPTS that relieves much burden to the data-related problems. The study further presents three heuristics ( saving technique,proximity priority searching technique,and insertion technique) for VRPTS,developed by extending and modifying the existing heuristics for conventional VRP. The results of computational experiments demonstrate that the proposed estimation model performs well and the saving technique is the best among the three heuristics. 相似文献
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Florian Turbant Jehan Waeytens Camille Campidelli Marianne Bombled Denis Martinez Axelle Grlard Birgit Habenstein Vincent Raussens Marisela Velez Frank Wien Vronique Arluison 《International journal of molecular sciences》2022,23(15)
Hfq is a pleiotropic regulator that mediates several aspects of bacterial RNA metabolism. The protein notably regulates translation efficiency and RNA decay in Gram-negative bacteria, usually via its interaction with small regulatory RNAs. Previously, we showed that the Hfq C-terminal region forms an amyloid-like structure and that these fibrils interact with membranes. The immediate consequence of this interaction is a disruption of the membrane, but the effect on Hfq structure was unknown. To investigate details of the mechanism of interaction, the present work uses different in vitro biophysical approaches. We show that the Hfq C-terminal region influences membrane integrity and, conversely, that the membrane specifically affects the amyloid assembly. The reported effect of this bacterial master regulator on membrane integrity is discussed in light of the possible consequence on small regulatory RNA-based regulation. 相似文献
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We report the first Polish representative of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), lukS/F-PV-positive, encoding the ermB gene, as a genetic determinant of constitutive resistance to macrolides, lincosamides, and streptogramin B antibiotics, cMLS-B. This is the first detection of the CA-MRSA strain responsible for nosocomial infection in the Warsaw Clinical Hospital. Resistance to β-lactams associates with a composite genetic element, SCCmec cassette type VT (5C2&5). We assigned the strain to sequence type ST338 (single-locus variant of ST59), clonal complex CC59, spa-type t437, and agr-type I. Genomic-based comparison was designated SO574/12 as an international Taiwan clone, which has been so far described mainly in the Asia-Pacific region. The ermB gene locates on the chromosome within the 14,690 bp mobile element structure, i.e., the MESPM1-like structure, which also encodes aminoglycoside- and streptothricin-resistance genes. The MESPM1-like structure is a composite transposon containing Tn551, flanked by direct repeats of IS1216V insertion sequences, which probably originates from Enterococcus. The ermB is preceded by the 273 bp regulatory region that contains the regulatory 84 bp ermBL ORF, encoding the 27 amino acid leader peptides. The latest research suggests that a new leader peptide, ermBL2, also exists in the ermB regulatory region. Therefore, the detailed function of ermBL2 requires further investigations. 相似文献
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提出经向夹衬加强筋机织物的结构,介绍其形成原理及方法,并通过实验及讨论,提出双梭口织机引纬、打纬、送经和卷取机构的改造方案。该结构改善了纤维或纱线在织物及其复合材料中的空间分布形态,从而也能加强其物理机械性能,扩大应用领域。 相似文献